Sequential gearbox



FIG. 1 is a top plan view of a sequential gearbox showing my new design;

FIG. 2 is a bottom view thereof;

FIG. 3 is a right elevation view thereof;

FIG. 4 is a left elevation view thereof;

FIG. 5 is a front elevation view thereof;

FIG. 6 is a rear elevation view thereof; and,

FIG. 7 is a perspective view thereof. 

CLAIM I claim the ornamental design for a sequential gearbox, as shown and described. 